It is generally known to supply commercial aircraft with conditioned air for heating and cooling when the aircraft is stationary at a gate. In this application, the terminal or gate is meant to refer to any place that an aircraft receives or discharges passengers or cargo. This may be by way of a telescoping corridor (also referred to as a walkway, bridge way, jet bridge), stairs, or any other facility.
As illustrated diagrammatically in FIG. 1, typically, conditioned air is supplied to the aircraft 14 via a flexible hose 10 connected to a pre-conditioned air (PCA) 12 unit associated with the gate that is a part of the airport terminal. The PCA unit 12 may produce heated air or cooled air depending on the needs of the aircraft 14 it is servicing. The PCA outputs its air into a duct that may be rigid or flexible, and then the air is delivered from the gate to the aircraft with a flexible and usually insulated air hose 10 which is installed to the aircraft 14 by a service technician 16 while the aircraft is parked at the gate.
Devices for deploying and retracting a hose are shown in U.S. Pat. Nos. 6,821,201, 6,776,705, and 6,834,668 to Bombardi et al., which are hereby incorporated herein by reference in their entirety. An improved hose management system is described in U.S. patent application Ser. No. 12/025,022 filed Feb. 2, 2008 by Wright et. al, and assigned to the assignee of the present application, which is hereby incorporated herein by reference in its entirety. Structures of an air hose are shown in detail in U.S. patent application Ser. No. 13/030,963 filed Feb. 18, 2011, assigned to the assignee of the present application, which is incorporated by reference herein in its entirety. Structures of a coupling for use between a hose and aircraft are shown in detail in U.S. patent application Ser. No. 12/861,298 filed Aug. 23, 2010, assigned to the assignee of the present application, which is incorporated by reference herein in its entirety.
A difficulty that arises with ventilation systems of this kind is the possible introduction of foreign matter into the air stream. The foreign matter can include paper, plastic, lint or other typical material that clogs an air flow path. If this matter invades the air delivery systems of the aircraft it can be very expensive to remove, not just as a result of labor cost but also because the cleaning process necessitates airplane downtime. Thus, there is a need for an improved air handling system that can reduce the amount of foreign matter introduced into airplane ventilation systems to thus reduce expenses and downtime.
Although this background has described the use of air hoses with reference to servicing aircraft, similar hose has other uses, for example ventilating confined working spaces such as sewers, tanks, and utility tunnels, and principles of the present invention are equally applicable in such contexts.